Editorial
Fusion surgery for lumbar spinal stenosis? Fay E. A. Greenway, Marios C. Papadopoulos Department of Neurosurgery, Atkinson Morley Wing, St George’s University Hospital, London, UK Correspondence to: Prof. Marios C. Papadopoulos. Department of Neurosurgery, Atkinson Morley Wing, St George’s University Hospital, London SW17 0QT, UK. Email: [email protected]. Submitted Jun 15, 2016. Accepted for publication Jun 25, 2016. doi: 10.21037/jss.2016.06.08 View this article at: http://dx.doi.org/10.21037/jss.2016.06.08
Low back pain is a leading cause of disability worldwide and a major source of other medical problems including depression and substance misuse. In 2011–2012, lumbar spinal stenosis was diagnosed in 22,759 people in the UK and over 15,000 operations were performed for decompression of the lumbar spine (UK Hospital Episodes Statistics). Spinal stenosis is typically caused by degenerative changes of the facet joint and ligamentum flavum leading to narrowing of the spinal canal and associated neural compression. This results in leg pain and neurogenic claudication, thus restricting the patients’ walking ability and overall quality of life. Standard UK neurosurgical training for the management of lumbar canal stenosis has been for decompressive laminectomy with undercutting facetectomy to clear the lateral recesses. Concurrent fusion is only performed if there is evidence of dynamic instability on flexion/extension radiographs. However, there is wide variation in views and practice across the globe, with some centres routinely performing instrumented fusion. Some studies have suggested that degenerative spondylolisthesis is associated with a risk of progressive instability through the manipulation and destruction of spinal elements during decompressive surgery, and thus that fusion should accompany simple decompression (1-4). However, the validity of these studies has since been questioned (5,6). Several cohort studies (5,7-10) did not find any substantial benefit of combining fusion with the decompression, even in the presence of spondylolisthesis. Försth et al. 2016 (11) completed a randomized controlled trial in Sweden, comparing decompression alone with decompression and fusion for patients with lumbar canal
© OSS Press Ltd. All rights reserved.
stenosis, with and without spondylolisthesis. They conclude that there is no significant difference in the effectiveness of these treatments, and that combining fusion with the decompression adds little value to the patient outcome. Försth et al. randomly assigned 247 patients between the ages of 50 and 80 with lumbar spinal stenosis, with or without degenerative spondylolisthesis, to undergo either decompression alone or decompression with fusion surgery. Two hundred and twenty eight patients were included in the per-protocol analysis—111 had fusion with decompression and 117 had decompression alone. The patients were stratified into fusion with spondylolisthesis, fusion without spondylolisthesis, decompression with spondylolisthesis, and decompression without spondylolisthesis. One point of note is that assessment of spondylolisthesis was performed using lateral radiographs—without dynamic views. This is contrary to our practice where we would typically use flexion and extension views as part of the work up process to help decide management. They defined degenerative spondylolisthesis as the presence of forward slip of a vertebra of at least 3mm in relation to the vertebra below it. The primary outcome measure was the Oswestry Disability Index (ODI), an internationally recognised and validated measure used to assess disability related to low back pain. Two-year outcomes showed no statistically significant difference between the treatment groups with a mean score of 27 for fusion-decompression group versus 24 for decompression alone. When stratified into the presence or absence of spondylolisthesis, outcomes were similar to the overall analysis. Further post-hoc analysis of the spondylolisthesis group showed no significant difference in ODI score between the fusion-decompression versus the decompression alone groups at baseline pre-op or at 2 years.
jss.osspress.com
J Spine Surg 2016;2(2):154-157
Journal of Spine Surgery, Vol 2, No 2 June 2016
There was no significant difference in results of the six minute walking test at 2 years, or in the walking distance between the two groups. One hundred and forty four patients were eligible for inclusion in the five year follow up assessment, of those 138 provided information. There was no significant difference between the fusion-decompression and the decompression alone groups; and results were similar with and without spondylolisthesis. In the same issue of NEJM, Ghogawala et al. (12) published their data on the same subject. This was a randomised controlled trial assigning 66 patients, between the ages of 50 and 80, to either decompression alone or decompression and fusion. However, this trial only included patients with grade I spondylolisthesis, as seen on lateral lumbar radiographs. Their primary outcome measure was the physical component score of the SF-36 questionnaire and secondary outcome the ODI. The SF-36 physical component score is a section of the internationally validated Medical Outcomes Study 36-item Short Form Heath Survey—a survey completed by the patient themselves. The improvement in the physical component SF36 scores between the groups was significantly different, with the fusion group having a greater improvement (P=0.046). The ODI score differences between the two groups were not statistically significant. As one might expect, the rate of complications in fusiondecompression surgery was higher than decompression alone. A large analysis of registry data showed the addition of fusion doubled the risk of severe adverse events (13). In addition to the complication rate, length of hospital stay and costs associated with fusion should also be considered. All healthcare systems have financial and economic pressures; one should bear this in mind when planning services to ensure that the best, evidence-based, cost-effective treatments are offered. Försth et al. reported dural tears in 11% for both the fusion-decompression and decompression alone groups. Though not statistically significant, post-operative wound infections requiring antibiotics alone occurred in 10% of the fusion-decompression group and in 4% of the decompression alone group. Both Försth and Ghogawala demonstrated statistically significant differences in regards to blood loss and operating times (Ghogawala—blood loss: fusiondecompression 513 mL vs. decompression alone 83 mL; operating time: fusion-decompression 289 minutes vs. decompression alone 124 minutes; P values
Fusion surgery for lumbar spinal stenosis? Fay E. A. Greenway, Marios C. Papadopoulos Department of Neurosurgery, Atkinson Morley Wing, St George’s University Hospital, London, UK Correspondence to: Prof. Marios C. Papadopoulos. Department of Neurosurgery, Atkinson Morley Wing, St George’s University Hospital, London SW17 0QT, UK. Email: [email protected]. Submitted Jun 15, 2016. Accepted for publication Jun 25, 2016. doi: 10.21037/jss.2016.06.08 View this article at: http://dx.doi.org/10.21037/jss.2016.06.08
Low back pain is a leading cause of disability worldwide and a major source of other medical problems including depression and substance misuse. In 2011–2012, lumbar spinal stenosis was diagnosed in 22,759 people in the UK and over 15,000 operations were performed for decompression of the lumbar spine (UK Hospital Episodes Statistics). Spinal stenosis is typically caused by degenerative changes of the facet joint and ligamentum flavum leading to narrowing of the spinal canal and associated neural compression. This results in leg pain and neurogenic claudication, thus restricting the patients’ walking ability and overall quality of life. Standard UK neurosurgical training for the management of lumbar canal stenosis has been for decompressive laminectomy with undercutting facetectomy to clear the lateral recesses. Concurrent fusion is only performed if there is evidence of dynamic instability on flexion/extension radiographs. However, there is wide variation in views and practice across the globe, with some centres routinely performing instrumented fusion. Some studies have suggested that degenerative spondylolisthesis is associated with a risk of progressive instability through the manipulation and destruction of spinal elements during decompressive surgery, and thus that fusion should accompany simple decompression (1-4). However, the validity of these studies has since been questioned (5,6). Several cohort studies (5,7-10) did not find any substantial benefit of combining fusion with the decompression, even in the presence of spondylolisthesis. Försth et al. 2016 (11) completed a randomized controlled trial in Sweden, comparing decompression alone with decompression and fusion for patients with lumbar canal
© OSS Press Ltd. All rights reserved.
stenosis, with and without spondylolisthesis. They conclude that there is no significant difference in the effectiveness of these treatments, and that combining fusion with the decompression adds little value to the patient outcome. Försth et al. randomly assigned 247 patients between the ages of 50 and 80 with lumbar spinal stenosis, with or without degenerative spondylolisthesis, to undergo either decompression alone or decompression with fusion surgery. Two hundred and twenty eight patients were included in the per-protocol analysis—111 had fusion with decompression and 117 had decompression alone. The patients were stratified into fusion with spondylolisthesis, fusion without spondylolisthesis, decompression with spondylolisthesis, and decompression without spondylolisthesis. One point of note is that assessment of spondylolisthesis was performed using lateral radiographs—without dynamic views. This is contrary to our practice where we would typically use flexion and extension views as part of the work up process to help decide management. They defined degenerative spondylolisthesis as the presence of forward slip of a vertebra of at least 3mm in relation to the vertebra below it. The primary outcome measure was the Oswestry Disability Index (ODI), an internationally recognised and validated measure used to assess disability related to low back pain. Two-year outcomes showed no statistically significant difference between the treatment groups with a mean score of 27 for fusion-decompression group versus 24 for decompression alone. When stratified into the presence or absence of spondylolisthesis, outcomes were similar to the overall analysis. Further post-hoc analysis of the spondylolisthesis group showed no significant difference in ODI score between the fusion-decompression versus the decompression alone groups at baseline pre-op or at 2 years.
jss.osspress.com
J Spine Surg 2016;2(2):154-157
Journal of Spine Surgery, Vol 2, No 2 June 2016
There was no significant difference in results of the six minute walking test at 2 years, or in the walking distance between the two groups. One hundred and forty four patients were eligible for inclusion in the five year follow up assessment, of those 138 provided information. There was no significant difference between the fusion-decompression and the decompression alone groups; and results were similar with and without spondylolisthesis. In the same issue of NEJM, Ghogawala et al. (12) published their data on the same subject. This was a randomised controlled trial assigning 66 patients, between the ages of 50 and 80, to either decompression alone or decompression and fusion. However, this trial only included patients with grade I spondylolisthesis, as seen on lateral lumbar radiographs. Their primary outcome measure was the physical component score of the SF-36 questionnaire and secondary outcome the ODI. The SF-36 physical component score is a section of the internationally validated Medical Outcomes Study 36-item Short Form Heath Survey—a survey completed by the patient themselves. The improvement in the physical component SF36 scores between the groups was significantly different, with the fusion group having a greater improvement (P=0.046). The ODI score differences between the two groups were not statistically significant. As one might expect, the rate of complications in fusiondecompression surgery was higher than decompression alone. A large analysis of registry data showed the addition of fusion doubled the risk of severe adverse events (13). In addition to the complication rate, length of hospital stay and costs associated with fusion should also be considered. All healthcare systems have financial and economic pressures; one should bear this in mind when planning services to ensure that the best, evidence-based, cost-effective treatments are offered. Försth et al. reported dural tears in 11% for both the fusion-decompression and decompression alone groups. Though not statistically significant, post-operative wound infections requiring antibiotics alone occurred in 10% of the fusion-decompression group and in 4% of the decompression alone group. Both Försth and Ghogawala demonstrated statistically significant differences in regards to blood loss and operating times (Ghogawala—blood loss: fusiondecompression 513 mL vs. decompression alone 83 mL; operating time: fusion-decompression 289 minutes vs. decompression alone 124 minutes; P values
